High-temperature-resistant rubber material for LED light source packaging and preparation method thereof
By combining thiofluorene-type bis(diazanaphthyl)-benzimidazole modified polyimide with EPDM rubber, the problem of physical property degradation of LED packaging materials at high temperatures was solved, and the heat resistance of the material and the reliability of LEDs were improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUANGDONG SUOLIGHT TECH CO LTD
- Filing Date
- 2026-03-18
- Publication Date
- 2026-05-29
AI Technical Summary
Existing LED packaging materials will experience physical property degradation under high temperature environments, affecting the stable operation of LEDs.
A thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide was used to composite with EPDM rubber. By introducing thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide during the preparation process, the rigidity of the polymer backbone and the interaction between molecular chains were enhanced, thereby improving the heat resistance of the material.
It significantly enhances the reliability and durability of LED packaging materials in high-temperature environments, and extends the working life of LEDs.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of rubber materials technology, specifically to a high-temperature resistant rubber material for LED light source packaging and its preparation method. Background Technology
[0002] In modern technology applications, LED light sources are widely used in various lighting fields due to their advantages such as high efficiency, energy saving, and environmental friendliness. To improve the reliability and application range of LED lighting, packaging technology has become a key element. Packaging materials need to protect the LED from the influence of the external environment while also withstanding various extreme conditions. Traditional packaging materials experience physical property degradation when exposed to high temperatures, thus affecting the stable operation of the LED. Therefore, this invention provides a high-temperature resistant rubber material for LED light source packaging and its preparation method, improving the durability and reliability of LED lamps in extreme environments. Summary of the Invention
[0003] In order to overcome the above-mentioned technical problems, the present invention aims to provide a high-temperature resistant rubber material for LED light source packaging and its preparation method, which solves the problem that the physical properties of existing LED packaging materials deteriorate under high-temperature environments, thereby affecting the stable operation of LEDs.
[0004] The objective of this invention can be achieved through the following technical solutions: In a first aspect, this application provides a high-temperature resistant rubber material for LED light source packaging, comprising the following parts by weight: 40-60 parts of EPDM rubber, 15-25 parts of thiofluorene-type bis(diazaphthyl)-benzimidazole modified polyimide, 2-3 parts of vulcanizing agent, 10-20 parts of silica, 0.3-0.6 parts of antioxidant, and 2-4 parts of stearic acid; The thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide is prepared by the following steps: Step A1: Add iron powder, ammonium chloride, ethanol and deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen for protection and stir under reflux for 20-30 min. Dissolve 4-nitrophthalic anhydride in methanol and add it to the flask. React for 4-5 h. Filter with diatomaceous earth, remove methanol and ethanol by rotary evaporation, filter again, wash with anhydrous ethanol 3-4 times, and dry to obtain aminophthalic anhydride.
[0005] Step A2: Add aminophthalic anhydride, anhydrous aluminum chloride and 1,2-dichloroethane to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Stir at 80°C for 30 min, add thiofluorene and react for 6 h. Pour into ice water containing concentrated hydrochloric acid, remove 1,2-dichloroethane by vacuum distillation, and dry in a drying oven at 80°C to obtain intermediate product 1.
[0006] Step A3: Add intermediate product 1 and anhydrous ethanol to a three-necked flask equipped with a thermometer and a constant pressure dropping funnel. Add hydrazine hydrate and acetic acid dropwise and react at 80°C for 4-5 hours. Filter and wash with ethanol and deionized water 4-6 times in sequence. Place in a drying oven and dry at 80°C for 24 hours to obtain intermediate product 2.
[0007] Step A4: Add intermediate product 2 and anhydrous ethanol to a three-necked flask equipped with a stirrer, thermometer and reflux condenser, stir for 30 min, dissolve p-aldehyde benzoic acid in ethanol and add it to the flask, add glacial acetic acid and heat to reflux for 4-6 h, cool and add to deionized water and filter under reduced pressure, recrystallize with ethyl acetate / petroleum ether mixed solvent, dry to obtain intermediate product 3;
[0008] Step A5: Add intermediate product 3,4-nitro-o-phenylenediamine and hydroquinone to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Add hydrochloric acid solution and trifluoromethanesulfonic acid, purge with nitrogen for protection, stir at 120°C for 30 min, raise the temperature to 130°C and stir for 6 h, cool, adjust the pH to 9-10 with sodium bicarbonate solution, stir until the bubbles disappear, filter, wash 6-8 times with deionized water, wash 3 times with ethanol, dry to obtain intermediate product 4;
[0009] Step A6: Add iron powder, ammonium chloride, ethanol and deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen for protection and stir under reflux for 20-30 min. Dissolve intermediate product 4 in dimethylacetamide and add it to the flask. React for 4-5 h. Filter with diatomaceous earth and remove dimethylacetamide and ethanol by rotary evaporation. Filter again, wash with anhydrous ethanol 3-4 times, and dry to obtain intermediate product 5.
[0010] Step A7: Add intermediate product 5 and anhydrous N,N-dimethylacetamide to a two-necked flask equipped with a stirrer, stir for 10-20 min, add 4,4'-(hexafluoroisopropene)phthalic anhydride and stir for 8 h, add pyridine and acetic anhydride and stir for 18 h, add cold methanol to precipitate, filter and dry, add to N,N-dimethylacetamide and wash dropwise in ethanol 3 times, dry to obtain thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide.
[0011]
[0012] As a further aspect of the present invention: the ratio of iron powder, ammonium chloride, ethanol, deionized water, 4-nitrophthalic anhydride and methanol used in step A1 is 100-200 mmol: 50-100 mmol: 360-720 mL: 120-240 mL: 25-50 mmol: 60-120 mL.
[0013] As a further aspect of the present invention: the ratio of aminophthalic anhydride, anhydrous aluminum chloride, 1,2-dichloroethane and thiofluorene in step A2 is 50-100 mmol: 200-400 mmol: 500-1000 mL: 25-50 mmol.
[0014] As a further aspect of the present invention: the mass fraction of the concentrated hydrochloric acid in step A2 is 36%.
[0015] As a further aspect of the present invention: the mass fraction of the sodium bicarbonate solution in step A2 is 10%.
[0016] As a further aspect of the present invention: in step A2, the volume ratio of concentrated hydrochloric acid to ice water in the ice water containing concentrated hydrochloric acid is 1:5.
[0017] As a further aspect of the present invention: the ratio of intermediate product 1, anhydrous ethanol, hydrazine hydrate and acetic acid in step A3 is 12.5-25 mmol: 500-1000 mL: 1.875-3.75 g: 5-10 mmol.
[0018] As a further aspect of the present invention: the mass fraction of hydrazine hydrate in step A3 is 80%.
[0019] As a further aspect of the present invention: the ratio of intermediate product 2, anhydrous ethanol, p-aldehyde benzoic acid, ethanol and glacial acetic acid in step A4 is 10-20 mmol: 300-600 mL: 24-48 mmol: 24-48 mL: 24-48 mmol.
[0020] As a further aspect of the present invention: the volume ratio of ethyl acetate to petroleum ether in the ethyl acetate / petroleum ether mixed solvent in step A4 is 1:3.
[0021] As a further aspect of the present invention: the ratio of the intermediate product 3,4-nitro-o-phenylenediamine, hydroquinone, hydrochloric acid solution and trifluoromethanesulfonic acid in step A5 is 10-20 mmol: 20-40 mmol: 2-4 mmol: 120-240 mL: 5-10 mmol.
[0022] As a further aspect of the present invention: the molar concentration of the hydrochloric acid solution in step A5 is 6 mol / L.
[0023] As a further aspect of the present invention: the mass fraction of the sodium bicarbonate solution in step A5 is 10%.
[0024] As a further aspect of the present invention: the ratio of iron powder, ammonium chloride, ethanol, deionized water, intermediate product 4 and dimethylacetamide in step A6 is 200-400 mmol: 100-200 mmol: 360-720 mL: 120-240 mL: 25-50 mmol: 60-120 mL.
[0025] As a further aspect of the present invention: the ratio of intermediate product 5, anhydrous N,N-dimethylacetamide, 4,4'-(hexafluoroisopropene)phthalic anhydride, pyridine and acetic anhydride in step A7 is 10-20 mmol: 50-100 mL: 10-20 mmol: 40-80 mmol: 25-50 mmol.
[0026] Secondly, a method for preparing a high-temperature resistant rubber material for LED light source packaging includes the following steps: Step 1: Weigh out 40-60 parts by weight of EPDM rubber, 15-25 parts by weight of thiofluorene-type bis(diazanaphthyl)-benzimidazole modified polyimide, 2-3 parts by weight of vulcanizing agent, 10-20 parts by weight of silica, 0.3-0.6 parts by weight of antioxidant, and 2-4 parts by weight of stearic acid, and set aside. The EPDM rubber is EPDM 3092PM; the vulcanizing agent is 1,3-bis(tert-butylperoxyisopropyl)benzene; the antioxidant is antioxidant 2246; and the stearic acid is stearic acid 1810. Step 2: Add EPDM rubber and thiofluorene-type bis(diazanaphthol)-benzimidazole modified polyimide into a two-roll mill and mix at 60-70℃ for 10-20 minutes to obtain a premix. Step 3: Add the premix, silica, stearic acid and antioxidant to the open mill and mix at 100-110℃ for 5-10 minutes. Cool down to 40-50℃, add the vulcanizing agent and mix for 20-30 minutes. Place on a flat vulcanizing machine to vulcanize and mold, and obtain the high-temperature resistant rubber material for LED light source encapsulation.
[0027] Beneficial effects of this invention: The present invention discloses a high-temperature resistant rubber material for LED light source packaging, which is synthesized by combining a thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide with EPDM rubber. This material can effectively resist aging reactions at high temperatures, improve the high-temperature resistance of the material, and thus significantly enhance the reliability of LED packaging in high-temperature environments.
[0028] A high-temperature resistant rubber material for LED light source encapsulation was prepared by first preparing aminophthalic anhydride from 4-nitrophthalic anhydride. The aminophthalic anhydride reacted with 1,2-dichloroethane to obtain intermediate 1. Intermediate 1 reacted with hydrazine hydrate to obtain intermediate 2. The amino group in intermediate 2 reacted with the aldehyde group of p-aldehyde benzoic acid to obtain intermediate 3. The carboxyl group in intermediate 3 underwent a cyclization reaction with the o-diamino group in 4-nitro-o-phenylenediamine to obtain intermediate 4. The nitro group in intermediate 4 was reduced to obtain an amino-containing intermediate 5. Intermediate 5 was polymerized with 4,4'-(hexafluoroisopropene)phthalic anhydride to obtain a thiofluorene-type bis(diazanaphthone). Benzimidazole-modified polyimide, with its thiofluorene-type bis(diazanaphthone) structure, effectively reduces the flexible groups in the polymer backbone and increases the rigid bis(diazanaphthone) structural units, thereby significantly enhancing the overall rigidity of the polymer backbone. Simultaneously, the conjugated structure of thiofluorene strengthens the interactions between molecular chains, further improving the polymer's heat resistance. The introduction of benzimidazole heterocycles into the polymer structure, with their rigid structure and asymmetric charge distribution, can form intermolecular hydrogen bonds, significantly improving the material's thermal stability. Furthermore, the polyimide itself possesses excellent heat resistance, and the synergistic effect enhances the heat resistance of the rubber material, thereby improving the thermal management efficiency of LED packaging and extending the LED's lifespan. Detailed Implementation
[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention. Example
[0030] This embodiment describes a method for preparing a high-temperature resistant rubber material for LED light source packaging, including the following steps: Step A1: Add 100 mmol iron powder, 50 mmol ammonium chloride, 360 mL ethanol and 120 mL deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen and stir under reflux for 20 min. Dissolve 25 mmol 4-nitrophthalic anhydride in 60 mL methanol and add it to the flask. React for 4 h. Filter with diatomaceous earth, remove methanol and ethanol by rotary evaporation, filter again, wash three times with anhydrous ethanol, and dry to obtain aminophthalic anhydride. Step A2: Add 50 mmol of aminophthalic anhydride, 200 mmol of anhydrous aluminum chloride and 500 mL of 1,2-dichloroethane to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Stir at 80 °C for 30 min, add 25 mmol of thiofluorene and react for 6 h. Pour into ice water containing concentrated hydrochloric acid, remove 1,2-dichloroethane by vacuum distillation, and dry in a drying oven at 80 °C to obtain intermediate product 1. Step A3: Add 12.5 mmol of intermediate product 1 and 500 mL of anhydrous ethanol to a three-necked flask equipped with a thermometer and a constant pressure dropping funnel. Add 1.875 g of hydrazine hydrate and 5 mmol of acetic acid dropwise and react at 80 °C for 4 h. Filter, wash with ethanol and deionized water 4 times in sequence, and dry in a drying oven at 80 °C for 24 h to obtain intermediate product 2. Step A4: Add 10 mmol of intermediate product 2 and 300 mL of anhydrous ethanol to a three-necked flask equipped with a stirrer, thermometer and reflux condenser. Stir for 30 min. Dissolve 24 mmol of p-aldehyde benzoic acid in 24 mL of ethanol and add it to the flask. Add 24 mmol of glacial acetic acid and heat to reflux for 4 h. Cool and add to deionized water. Filter under reduced pressure. Recrystallize with ethyl acetate / petroleum ether mixed solvent and dry to obtain intermediate product 3. Step A5: Add 10 mmol of intermediate product 3, 20 mmol of 4-nitro-o-phenylenediamine and 2 mmol of hydroquinone to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Add 120 mL of hydrochloric acid solution and 5 mmol of trifluoromethanesulfonic acid. Purge with nitrogen for protection and stir at 120 °C for 30 min. Increase the temperature to 130 °C and stir for 6 h. Cool and adjust the pH to 9 with sodium bicarbonate solution. Stir until the bubbles disappear. Filter, wash 6 times with deionized water and 3 times with ethanol. Dry to obtain intermediate product 4. Step A6: Add 200 mmol iron powder, 100 mmol ammonium chloride, 360 mL ethanol and 120 mL deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen and stir under reflux for 20 min. Dissolve 25 mmol of intermediate product 4 in 60 mL dimethylacetamide and add it to the flask. React for 4 h. Filter with diatomaceous earth, remove dimethylacetamide and ethanol by rotary evaporation, filter, wash three times with anhydrous ethanol, and dry to obtain intermediate product 5. Step A7: Add 10 mmol of intermediate product 5 and 50 mL of anhydrous N,N-dimethylacetamide to a two-necked flask equipped with a stirrer, stir for 10 min, add 10 mmol of 4,4'-(hexafluoroisopropene)phthalic anhydride and stir for 8 h, add 40 mmol of pyridine and 25 mmol of acetic anhydride and stir for 18 h, precipitate in cold methanol, filter and dry, add to N,N-dimethylacetamide and wash three times with ethanol, dry to obtain thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide; Step A8: Weigh out 40 parts by weight of EPDM rubber, 15 parts by weight of thiofluorene-type bis(diazanaphthyl)-benzimidazole modified polyimide, 2 parts by weight of vulcanizing agent, 10 parts by weight of silica, 0.3 parts by weight of antioxidant, and 2 parts by weight of stearic acid, and set aside; wherein, the type of EPDM rubber is EPDM 3092PM; the vulcanizing agent is 1,3-bis(tert-butylperoxyisopropyl)benzene; the antioxidant is antioxidant 2246; and the stearic acid is stearic acid 1810; Step A9: Add EPDM rubber and thiofluorene-type bis(diazanaphthol)-benzimidazole modified polyimide into a two-roll mill and mix at 60°C for 10 minutes to obtain a premix. Step A10: Add the premix, silica, stearic acid and antioxidant to the open mill, mix at 100°C for 5 minutes, cool to 40°C, add vulcanizing agent and mix for 20 minutes, place on a flat vulcanizing machine to vulcanize and mold, and obtain high temperature resistant rubber material for LED light source encapsulation. Example
[0031] This embodiment describes a method for preparing a high-temperature resistant rubber material for LED light source packaging, including the following steps: Step A1: Add 150 mmol of iron powder, 75 mmol of ammonium chloride, 540 mL of ethanol and 180 mL of deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen and stir under reflux for 25 min. Dissolve 37.5 mmol of 4-nitrophthalic anhydride in 90 mL of methanol and add it to the flask. React for 4.5 h. Filter with diatomaceous earth, remove methanol and ethanol by rotary evaporation, filter again, wash four times with anhydrous ethanol, and dry to obtain aminophthalic anhydride. Step A2: 75 mmol aminophthalic anhydride, 300 mmol anhydrous aluminum chloride and 750 mL 1,2-dichloroethane were added to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. The mixture was stirred at 80 °C for 30 min, and 37.5 mmol thiofluorene was added and reacted for 6 h. The mixture was poured into ice water containing concentrated hydrochloric acid, and 1,2-dichloroethane was removed by vacuum distillation. The mixture was then dried in a drying oven at 80 °C to obtain intermediate product 1. Step A3: Add 18.75 mmol of intermediate product 1 and 750 mL of anhydrous ethanol to a three-necked flask equipped with a thermometer and a constant pressure dropping funnel. Add 2.8125 g of hydrazine hydrate and 7.5 mmol of acetic acid dropwise and react at 80 °C for 4.5 h. Filter, wash with ethanol and deionized water 5 times in sequence, and dry in a drying oven at 80 °C for 24 h to obtain intermediate product 2. Step A4: Add 15 mmol of intermediate product 2 and 450 mL of anhydrous ethanol to a three-necked flask equipped with a stirrer, thermometer and reflux condenser. Stir for 30 min. Dissolve 36 mmol of p-aldehyde benzoic acid in 36 mL of ethanol and add it to the flask. Add 36 mmol of glacial acetic acid and heat to reflux for 5 h. Cool and add to deionized water. Filter under reduced pressure. Recrystallize with ethyl acetate / petroleum ether mixed solvent and dry to obtain intermediate product 3. Step A5: Add 15 mmol of intermediate product 3, 30 mmol of 4-nitro-o-phenylenediamine and 3 mmol of hydroquinone to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Add 180 mL of hydrochloric acid solution and 7.5 mmol of trifluoromethanesulfonic acid. Purge with nitrogen for protection and stir at 120 °C for 30 min. Increase the temperature to 130 °C and stir for 6 h. Cool and adjust the pH to 9 with sodium bicarbonate solution. Stir until the bubbles disappear. Filter, wash 7 times with deionized water and 3 times with ethanol. Dry to obtain intermediate product 4. Step A6: Add 300 mmol iron powder, 150 mmol ammonium chloride, 540 mL ethanol and 180 mL deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen and stir under reflux for 25 min. Dissolve 37.5 mmol of intermediate product 4 in 90 mL dimethylacetamide and add it to the flask. React for 4.5 h. Filter with diatomaceous earth, remove dimethylacetamide and ethanol by rotary evaporation, filter, wash three times with anhydrous ethanol, and dry to obtain intermediate product 5. Step A7: Add 15 mmol of intermediate product 5 and 75 mL of anhydrous N,N-dimethylacetamide to a two-necked flask equipped with a stirrer, stir for 15 min, add 15 mmol of 4,4'-(hexafluoroisopropene) phthalic anhydride and stir for 8 h, add 60 mmol of pyridine and 37.5 mmol of acetic anhydride and stir for 18 h, precipitate in cold methanol, filter and dry, add to N,N-dimethylacetamide and wash three times with ethanol, dry to obtain thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide; Step A8: Weigh out 50 parts by weight of EPDM rubber, 20 parts by weight of thiofluorene-type bis(diazanaphthyl)-benzimidazole modified polyimide, 2.5 parts by weight of vulcanizing agent, 15 parts by weight of silica, 0.45 parts by weight of antioxidant, and 3 parts by weight of stearic acid, and set aside; wherein, the EPDM rubber is EPDM 3092PM; the vulcanizing agent is 1,3-bis(tert-butylperoxyisopropyl)benzene; the antioxidant is antioxidant 2246; and the stearic acid is stearic acid 1810; Step A9: Add EPDM rubber and thiofluorene-type bis(diazanaphthol)-benzimidazole modified polyimide into a two-roll mill and mix at 65°C for 15 minutes to obtain a premix. Step A10: Add the premix, silica, stearic acid and antioxidant to the open mill, mix at 105°C for 7 minutes, cool to 45°C, add vulcanizing agent and mix for 25 minutes, place on a flat vulcanizing machine to vulcanize and mold, and obtain high temperature resistant rubber material for LED light source encapsulation. Example
[0032] This embodiment describes a method for preparing a high-temperature resistant rubber material for LED light source packaging, including the following steps: Step A1: Add 200 mmol iron powder, 100 mmol ammonium chloride, 720 mL ethanol and 240 mL deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen and stir under reflux for 30 min. Dissolve 50 mmol 4-nitrophthalic anhydride in 120 mL methanol and add to the flask. React for 5 h. Filter with diatomaceous earth, remove methanol and ethanol by rotary evaporation, filter again, wash 4 times with anhydrous ethanol, and dry to obtain aminophthalic anhydride. Step A2: 100 mmol aminophthalic anhydride, 400 mmol anhydrous aluminum chloride and 1000 mL 1,2-dichloroethane were added to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. The mixture was stirred at 80 °C for 30 min, 50 mmol thiofluorene was added and the reaction was carried out for 6 h. The mixture was poured into ice water containing concentrated hydrochloric acid and the 1,2-dichloroethane was removed by vacuum distillation. The mixture was then dried in a drying oven at 80 °C to obtain intermediate product 1. Step A3: Add 25 mmol of intermediate product 1 and 1000 mL of anhydrous ethanol to a three-necked flask equipped with a thermometer and a constant pressure dropping funnel. Add 3.75 g of hydrazine hydrate and 10 mmol of acetic acid dropwise and react at 80 °C for 5 h. Filter and wash with ethanol and deionized water 6 times in sequence. Place in a drying oven and dry at 80 °C for 24 h to obtain intermediate product 2. Step A4: Add 20 mmol of intermediate product 2 and 600 mL of anhydrous ethanol to a three-necked flask equipped with a stirrer, thermometer and reflux condenser. Stir for 30 min. Dissolve 48 mmol of p-aldehyde benzoic acid in 48 mL of ethanol and add it to the flask. Add 48 mmol of glacial acetic acid and heat to reflux for 6 h. Cool and add to deionized water. Filter under reduced pressure. Recrystallize with ethyl acetate / petroleum ether mixed solvent and dry to obtain intermediate product 3. Step A5: Add 20 mmol of intermediate product 3, 40 mmol of 4-nitro-o-phenylenediamine and 4 mmol of hydroquinone to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Add 240 mL of hydrochloric acid solution and 10 mmol of trifluoromethanesulfonic acid. Purge with nitrogen for protection and stir at 120 °C for 30 min. Increase the temperature to 130 °C and stir for 6 h. Cool and adjust the pH to 10 with sodium bicarbonate solution. Stir until the bubbles disappear. Filter, wash 8 times with deionized water and 3 times with ethanol. Dry to obtain intermediate product 4. Step A6: Add 400 mmol iron powder, 200 mmol ammonium chloride, 720 mL ethanol and 240 mL deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen and stir under reflux for 30 min. Dissolve 50 mmol of intermediate product 4 in 120 mL dimethylacetamide and add to the flask. React for 5 h. Filter with diatomaceous earth, remove dimethylacetamide and ethanol by rotary evaporation, filter, wash 4 times with anhydrous ethanol, and dry to obtain intermediate product 5. Step A7: Add 20 mmol of intermediate product 5 and 100 mL of anhydrous N,N-dimethylacetamide to a two-necked flask equipped with a stirrer, stir for 20 min, add 20 mmol of 4,4'-(hexafluoroisopropene) phthalic anhydride and stir for 8 h, add 80 mmol of pyridine and 50 mmol of acetic anhydride and stir for 18 h, precipitate in cold methanol, filter and dry, add to N,N-dimethylacetamide and wash three times with ethanol, dry to obtain thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide; Step A8: Weigh out 60 parts by weight of EPDM rubber, 25 parts by weight of thiofluorene-type bis(diazanaphthyl)-benzimidazole modified polyimide, 3 parts by weight of vulcanizing agent, 20 parts by weight of silica, 0.6 parts by weight of antioxidant, and 4 parts by weight of stearic acid, and set aside; wherein, the EPDM rubber is EPDM 3092PM; the vulcanizing agent is 1,3-bis(tert-butylperoxyisopropyl)benzene; the antioxidant is antioxidant 2246; and the stearic acid is stearic acid 1810; Step A9: Add EPDM rubber and thiofluorene-type bis(diazanaphthol)-benzimidazole modified polyimide into a two-roll mill and mix at 70°C for 20 minutes to obtain a premix. Step A10: Add the premix, silica, stearic acid and antioxidant to the open mill, mix at 110°C for 10 minutes, cool to 50°C, add vulcanizing agent and mix for 30 minutes, place on a flat vulcanizing machine to vulcanize and mold, and obtain high temperature resistant rubber material for LED light source encapsulation.
[0033] Comparative Example 1: This comparative example illustrates a method for preparing a high-temperature resistant rubber material for LED light source packaging, comprising the following steps: Step A1: Add 200 mmol iron powder, 100 mmol ammonium chloride, 720 mL ethanol and 240 mL deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen and stir under reflux for 30 min. Dissolve 50 mmol 4-nitrophthalic anhydride in 120 mL methanol and add to the flask. React for 5 h. Filter with diatomaceous earth, remove methanol and ethanol by rotary evaporation, filter again, wash three times with anhydrous ethanol, and dry to obtain aminophthalic anhydride. Step A2: 100 mmol aminophthalic anhydride, 400 mmol anhydrous aluminum chloride and 1000 mL 1,2-dichloroethane were added to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. The mixture was stirred at 80 °C for 30 min, 50 mmol thiofluorene was added and the reaction was carried out for 6 h. The mixture was poured into ice water containing concentrated hydrochloric acid and the 1,2-dichloroethane was removed by vacuum distillation. The mixture was then dried in a drying oven at 80 °C to obtain intermediate product 1. Step A3: Add 25 mmol of intermediate product 1 and 1000 mL of anhydrous ethanol to a three-necked flask equipped with a thermometer and a constant pressure dropping funnel. Add 3.75 g of hydrazine hydrate and 10 mmol of acetic acid dropwise and react at 80 °C for 5 h. Filter and wash with ethanol and deionized water 6 times in sequence. Place in a drying oven and dry at 80 °C for 24 h to obtain intermediate product 2. Step A4: Add 20 mmol of intermediate 2 and 100 mL of anhydrous N,N-dimethylacetamide to a two-necked flask equipped with a stirrer, stir for 20 min, add 20 mmol of 4,4'-(hexafluoroisopropene)phthalic anhydride and stir for 8 h, add 80 mmol of pyridine and 50 mmol of acetic anhydride and stir for 18 h, precipitate in cold methanol, filter and dry, add to N,N-dimethylacetamide and wash three times with ethanol, dry to obtain thiofluorene-type bis(diazanaphthone) modified polyimide; Step A5: Weigh out 60 parts by weight of EPDM rubber, 25 parts by weight of thiofluorene-type bis(diazanaphthyl)-modified polyimide, 3 parts by weight of vulcanizing agent, 20 parts by weight of silica, 0.6 parts by weight of antioxidant, and 4 parts by weight of stearic acid, and set aside for later use; wherein, the type of EPDM rubber is EPDM 3092PM; the vulcanizing agent is 1,3-bis(tert-butylperoxyisopropyl)benzene; the antioxidant is antioxidant 2246; and the stearic acid is stearic acid 1810; Step A6: Add EPDM rubber and thiofluorene-type bis(diazanaphthol) modified polyimide to a two-roll mill and mix at 70°C for 20 minutes to obtain a premix. Step A7: Add the premix, silica, stearic acid and antioxidant to the open mill, mix at 110°C for 10 minutes, cool to 50°C, add vulcanizing agent and mix for 30 minutes, place on a flat vulcanizing machine to vulcanize and mold, and obtain high temperature resistant rubber material for LED light source encapsulation.
[0034] Comparative Example 2: This comparative example illustrates a method for preparing a high-temperature resistant rubber material for LED light source packaging, comprising the following steps: Step A1: Add 20 mmol of biphenyl dicarboxylic acid, 40 mmol of 4-nitro-o-phenylenediamine and 4 mmol of hydroquinone to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Add 240 mL of hydrochloric acid solution and 10 mmol of trifluoromethanesulfonic acid. Purge with nitrogen for protection and stir at 120 °C for 30 min. Increase the temperature to 130 °C and stir for 6 h. Cool and adjust the pH to 10 with sodium bicarbonate solution. Stir until the bubbles disappear. Filter, wash 8 times with deionized water and 3 times with ethanol. Dry to obtain intermediate product 1. Step A2: Add 400 mmol iron powder, 200 mmol ammonium chloride, 720 mL ethanol and 240 mL deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen and stir under reflux for 30 min. Dissolve 50 mmol of intermediate product 4 in 120 mL dimethylacetamide and add to the flask. React for 5 h. Filter with diatomaceous earth, remove dimethylacetamide and ethanol by rotary evaporation, filter, wash 4 times with anhydrous ethanol, and dry to obtain intermediate product 2. Step A3: Add 20 mmol of intermediate 2 and 100 mL of anhydrous N,N-dimethylacetamide to a two-necked flask equipped with a stirrer and stir for 20 min. Add 20 mmol of 4,4'-(hexafluoroisopropene)phthalic anhydride and stir for 8 h. Add 80 mmol of pyridine and 50 mmol of acetic anhydride and stir for 18 h. Add cold methanol to precipitate the product, filter and dry. Add N,N-dimethylacetamide and wash three times with ethanol. Dry to obtain benzimidazole modified polyimide. Step A4: Weigh out 60 parts by weight of EPDM rubber, 25 parts by weight of benzimidazole-modified polyimide, 3 parts by weight of vulcanizing agent, 20 parts by weight of silica, 0.6 parts by weight of antioxidant, and 4 parts by weight of stearic acid, and set aside. The EPDM rubber is EPDM 3092PM; the vulcanizing agent is 1,3-bis(tert-butylperoxyisopropyl)benzene; the antioxidant is antioxidant 2246; and the stearic acid is stearic acid 1810. Step A5: Add EPDM rubber and benzimidazole-modified polyimide into a two-roll mill and mix at 70°C for 20 minutes to obtain a premix. Step A6: Add the premix, silica, stearic acid and antioxidant to the open mill, mix at 110°C for 10 minutes, cool to 50°C, add the vulcanizing agent and mix for 30 minutes, place on a flat vulcanizing machine to vulcanize and mold, and obtain the high-temperature resistant rubber material for LED light source encapsulation.
[0035] Comparative Example 3: This comparative example illustrates a method for preparing a high-temperature resistant rubber material for LED light source packaging, comprising the following steps: Step A1: Add 200 mmol iron powder, 100 mmol ammonium chloride, 720 mL ethanol and 240 mL deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen and stir under reflux for 30 min. Dissolve 50 mmol 4-nitrophthalic anhydride in 120 mL methanol and add to the flask. React for 5 h. Filter with diatomaceous earth, remove methanol and ethanol by rotary evaporation, filter again, wash 4 times with anhydrous ethanol, and dry to obtain aminophthalic anhydride. Step A2: 100 mmol aminophthalic anhydride, 400 mmol anhydrous aluminum chloride and 1000 mL 1,2-dichloroethane were added to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. The mixture was stirred at 80 °C for 30 min, 50 mmol thiofluorene was added and the reaction was carried out for 6 h. The mixture was poured into ice water containing concentrated hydrochloric acid and the 1,2-dichloroethane was removed by vacuum distillation. The mixture was then dried in a drying oven at 80 °C to obtain intermediate product 1. Step A3: Add 25 mmol of intermediate product 1 and 1000 mL of anhydrous ethanol to a three-necked flask equipped with a thermometer and a constant pressure dropping funnel. Add 3.75 g of hydrazine hydrate and 10 mmol of acetic acid dropwise and react at 80 °C for 5 h. Filter and wash with ethanol and deionized water 6 times in sequence. Place in a drying oven and dry at 80 °C for 24 h to obtain intermediate product 2. Step A4: Add 20 mmol of intermediate product 2 and 600 mL of anhydrous ethanol to a three-necked flask equipped with a stirrer, thermometer and reflux condenser. Stir for 30 min. Dissolve 48 mmol of p-aldehyde benzoic acid in 48 mL of ethanol and add it to the flask. Add 48 mmol of glacial acetic acid and heat to reflux for 6 h. Cool and add to deionized water. Filter under reduced pressure. Recrystallize with ethyl acetate / petroleum ether mixed solvent and dry to obtain intermediate product 3. Step A5: Add 20 mmol of intermediate product 3, 40 mmol of 4-nitro-o-phenylenediamine and 4 mmol of hydroquinone to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Add 240 mL of hydrochloric acid solution and 10 mmol of trifluoromethanesulfonic acid. Purge with nitrogen for protection and stir at 120 °C for 30 min. Increase the temperature to 130 °C and stir for 6 h. Cool and adjust the pH to 10 with sodium bicarbonate solution. Stir until the bubbles disappear. Filter, wash 8 times with deionized water and 3 times with ethanol. Dry to obtain intermediate product 4. Step A6: Add 400 mmol iron powder, 200 mmol ammonium chloride, 720 mL ethanol and 240 mL deionized water to a three-necked flask equipped with a thermometer, stirrer and reflux condenser. Purge with nitrogen and reflux for 30 min. Dissolve 50 mmol of intermediate 4 in 120 mL dimethylacetamide and add to the flask. React for 5 h. Filter with diatomaceous earth and remove dimethylacetamide and ethanol by rotary evaporation. Filter, wash 4 times with anhydrous ethanol, and dry to obtain thiofluorene-type bis(diazanaphthone)-benzimidazole. Step A7: Weigh out 60 parts by weight of EPDM rubber, 15 parts by weight of thiofluorene-type bis(diazanaphthyl)-benzimidazole, 3 parts by weight of vulcanizing agent, 20 parts by weight of silica, 0.6 parts by weight of antioxidant, and 4 parts by weight of stearic acid, and set aside; wherein, the EPDM rubber is EPDM 3092PM; the vulcanizing agent is 1,3-bis(tert-butylperoxyisopropyl)benzene; the antioxidant is antioxidant 2246; and the stearic acid is stearic acid 1810; Step A8: Add EPDM rubber and thiofluorene-type bis(diazanaphthol)-benzimidazole to a two-roll mill and mix at 70°C for 20 minutes to obtain a premix. Step A9: Add the premix, silica, stearic acid and antioxidant to the open mill, mix at 110°C for 10 minutes, cool to 50°C, add vulcanizing agent and mix for 30 minutes, place on a flat vulcanizing machine to vulcanize and mold, and obtain high temperature resistant rubber material for LED light source encapsulation.
[0036] Comparative Example 4: This comparative example illustrates a method for preparing a high-temperature resistant rubber material for LED light source packaging, comprising the following steps: Step A1: Add 20 mmol of 4,4'-diaminobiphenyl and 100 mL of anhydrous N,N-dimethylacetamide to a two-necked flask equipped with a stirrer and stir for 20 min. Add 20 mmol of 4,4'-(hexafluoroisopropene)phthalic anhydride and stir for 8 h. Add 80 mmol of pyridine and 50 mmol of acetic anhydride and stir for 18 h. Add cold methanol to precipitate the product, filter and dry. Add N,N-dimethylacetamide and wash three times with ethanol. Dry to obtain polyimide. Step A2: Weigh out 60 parts by weight of EPDM rubber, 25 parts by weight of polyimide, 3 parts by weight of vulcanizing agent, 20 parts by weight of silica, 0.6 parts by weight of antioxidant, and 4 parts by weight of stearic acid, and set aside. The EPDM rubber is EPDM 3092PM; the vulcanizing agent is 1,3-bis(tert-butylperoxyisopropyl)benzene; the antioxidant is antioxidant 2246; and the stearic acid is stearic acid 1810. Step A3: Add EPDM rubber and polyimide to a two-roll mill and mix at 70°C for 20 minutes to obtain a premix. Step A4: Add the premix, silica, stearic acid and antioxidant to the open mill, mix at 110°C for 10 minutes, cool to 50°C, add the vulcanizing agent and mix for 30 minutes, place on a flat vulcanizing machine to vulcanize and mold, and obtain the high-temperature resistant rubber material for LED light source encapsulation.
[0037] Performance testing: The rubber materials of Examples 1-3 and Comparative Examples 1-4 were tested for tensile strength using an electronic tensile testing machine at a tensile speed of 500 mm / min, in accordance with GB / T 528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber". The Shore hardness values were measured using a rubber Shore hardness tester. The rubber materials of Examples 1-3 and Comparative Examples 1-4 were placed in hot air at 250°C for 25 hours. After being taken out, the tensile strength and Shore hardness were repeatedly tested. The Shore hardness change value was obtained by subtracting the Shore hardness before aging from the Shore hardness after aging.
[0038] Referring to the table above, based on the comparison between Examples 1-3 and Comparative Examples 1-4, it can be seen that the rubber material prepared by adding thiofluorene-type bis(diazanaphthone)-benzimidazole to modify polyimide has good high temperature resistance. Based on the comparison between Example 3 and Comparative Example 1, it can be seen that the Shore hardness change value of the rubber material prepared by adding thiofluorene-type bis(diazanaphthone-benzimidazole) modified polyimide is smaller than that of the rubber material prepared by adding thiofluorene-type bis(diazanaphthone-benzimidazole) modified polyimide, indicating that the rubber material prepared by adding thiofluorene-type bis(diazanaphthone-benzimidazole) modified polyimide has excellent high temperature resistance. Based on the comparison between Example 3 and Comparative Example 2, it can be seen that the Shore hardness change value of the rubber material prepared by adding thiofluorene-type bis(diazanaphthone-benzimidazole) modified polyimide is smaller than that of the rubber material prepared by adding benzimidazole modified polyimide, indicating that the rubber material prepared by adding thiofluorene-type bis(diazanaphthone-benzimidazole) modified polyimide has excellent high temperature resistance. Based on the comparison between Example 3 and Comparative Example 3, it can be seen that the Shore hardness change value of the rubber material prepared by adding thiofluorene-type bis(diazanaphthone-benzimidazole) modified polyimide is smaller than that of the rubber material prepared by adding thiofluorene-type bis(diazanaphthone-benzimidazole), indicating that the rubber material prepared by adding thiofluorene-type bis(diazanaphthone-benzimidazole) modified polyimide has excellent high temperature resistance. Based on the comparison between Example 3 and Comparative Example 4, it can be seen that the Shore hardness change value of the rubber material prepared by adding thiofluorene-type bis(diazanaphthone-benzimidazole) modified polyimide is smaller than that of the rubber material prepared by adding polyimide, indicating that the rubber material prepared by adding thiofluorene-type bis(diazanaphthone-benzimidazole) modified polyimide has excellent high temperature resistance.
[0039] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0040] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in this application, they should all fall within the protection scope of the present invention.
Claims
1. A high-temperature resistant rubber material for LED light source packaging, characterized in that, Includes the following components by weight: 40-60 parts of EPDM rubber, 15-25 parts of thiofluorene-type bis(diazaphthyl)-benzimidazole modified polyimide, 2-3 parts of vulcanizing agent, 10-20 parts of silica, 0.3-0.6 parts of antioxidant, and 2-4 parts of stearic acid; The thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide is prepared by the following steps: Step A1: Add iron powder, ammonium chloride, ethanol and deionized water to a flask, reflux and stir, dissolve 4-nitrophthalic anhydride in methanol and add it to the flask to react, to obtain aminophthalic anhydride; Step A2: Stir aminophthalic anhydride, anhydrous aluminum chloride and 1,2-dichloroethane, add thiofluorene to react and give intermediate product 1; Step A3: React intermediate 1, anhydrous ethanol, hydrazine hydrate, and acetic acid to obtain intermediate 2; Step A4: Add intermediate product 2 and anhydrous ethanol to a flask and stir. Dissolve p-aldehyde benzoic acid in ethanol and add it to the flask. Add glacial acetic acid and reflux to obtain intermediate product 3. Step A5: The intermediate product 3,4-nitro-o-phenylenediamine, hydroquinone, hydrochloric acid solution and trifluoromethanesulfonic acid are stirred and reacted to obtain intermediate product 4; Step A6: Add iron powder, ammonium chloride, ethanol and deionized water to a flask, reflux and stir, dissolve intermediate product 4 in dimethylacetamide and add it to the flask to react, to obtain intermediate product 5; Step A7: Stir intermediate 5 and anhydrous N,N-dimethylacetamide, add 4,4'-(hexafluoroisopropene) phthalic anhydride and stir, add pyridine and acetic anhydride and stir to react, to obtain thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide.
2. The high-temperature resistant rubber material for LED light source packaging according to claim 1, characterized in that, The ratio of iron powder, ammonium chloride, ethanol, deionized water, 4-nitrophthalic anhydride and methanol used in step A1 is 100-200 mmol: 50-100 mmol: 360-720 mL: 120-240 mL: 25-50 mmol: 60-120 mL.
3. The high-temperature resistant rubber material for LED light source packaging according to claim 1, characterized in that, The ratio of aminophthalic anhydride, anhydrous aluminum chloride, 1,2-dichloroethane and thiofluorene used in step A2 is 50-100 mmol: 200-400 mmol: 500-1000 mL: 25-50 mmol.
4. The high-temperature resistant rubber material for LED light source packaging according to claim 1, characterized in that, In step A3, the ratio of intermediate product 1, anhydrous ethanol, hydrazine hydrate, and acetic acid is 12.5-25 mmol: 500-1000 mL: 1.875-3.75 g: 5-10 mmol; the mass fraction of the hydrazine hydrate is 80%.
5. The high-temperature resistant rubber material for LED light source packaging according to claim 1, characterized in that, The ratio of intermediate product 2, anhydrous ethanol, p-aldehyde benzoic acid, ethanol and glacial acetic acid in step A4 is 10-20 mmol: 300-600 mL: 24-48 mmol: 24-48 mL: 24-48 mmol.
6. The high-temperature resistant rubber material for LED light source packaging according to claim 1, characterized in that, In step A5, the ratio of the intermediate product 3,4-nitro-o-phenylenediamine, hydroquinone, hydrochloric acid solution, and trifluoromethanesulfonic acid is 10-20 mmol: 20-40 mmol: 2-4 mmol: 120-240 mL: 5-10 mmol; the molar concentration of the hydrochloric acid solution is 6 mol / L.
7. The high-temperature resistant rubber material for LED light source packaging according to claim 1, characterized in that, The ratio of iron powder, ammonium chloride, ethanol, deionized water, intermediate product 4, and dimethylacetamide used in step A6 is 200-400 mmol: 100-200 mmol: 360-720 mL: 120-240 mL: 25-50 mmol: 60-120 mL.
8. The high-temperature resistant rubber material for LED light source packaging according to claim 1, characterized in that, The ratio of intermediate product 5, anhydrous N,N-dimethylacetamide, 4,4'-(hexafluoroisopropene)phthalic anhydride, pyridine, and acetic anhydride in step A7 is 10-20 mmol: 50-100 mL: 10-20 mmol: 40-80 mmol: 25-50 mmol.
9. A method for preparing a high-temperature resistant rubber material for LED light source packaging, characterized in that, The preparation of the high-temperature resistant rubber material for LED light source packaging as described in any one of claims 1-8 includes the following steps: Step 1: Weigh out 40-60 parts of EPDM rubber, 15-25 parts of thiofluorene-type bis(diazanaphthone)-benzimidazole modified polyimide, 2-3 parts of vulcanizing agent, 10-20 parts of silica, 0.3-0.6 parts of antioxidant, and 2-4 parts of stearic acid according to the following weight proportions, and set aside. Step 2: Add EPDM rubber and thiofluorene-type bis(diazanaphthol)-benzimidazole modified polyimide into a two-roll mill and mix at 60-70℃ for 10-20 minutes to obtain a premix. Step 3: Add the premix, silica, stearic acid and antioxidant to the open mill and mix at 100-110℃ for 5-10 minutes. Cool down to 40-50℃, add the vulcanizing agent and mix for 20-30 minutes. Place on a flat vulcanizing machine to vulcanize and mold, and obtain the high-temperature resistant rubber material for LED light source encapsulation.
10. The method for preparing a high-temperature resistant rubber material for LED light source packaging according to claim 9, characterized in that, The EPDM rubber is of type EPDM 3092PM; the vulcanizing agent is 1,3-bis(tert-butylperoxyisopropyl)benzene; the antioxidant is antioxidant 2246; and the stearic acid is stearic acid 1810.